Observations on emerging patterns of asthma in our society

Epidemiologic studies of temporal and geographic variation in asthma morbid ity have identified asthma as an important public health concern. Knowledge gained from these studies has resulted in intense focus on this condition by agencies such as the National Institutes of Health and the World Health Organization. In this report, studies of recent asthma trends and patterns are explored, These studies show increases in US prevalence through 1994. D ata on measures of morbidity show complex longitudinal patterns but are not able for large differences in emergency department services and hospitaliza tions by age and race. Very recent trends for US asthma mortality suggest w idening of an existing racial gap. Limited comparisons are possible between these US trends and international trends but do suggest that US increases in prevalence and mortality rates may reflect world-wide patterns. Also, wi thin the US, it is clear that geographic variation exists in asthma prevale nce, morbidity, and mortality rates. Changes in certain environmental risk factors and exposures may contribute to recent trends, but little informati on is available relating specific risk factors to either longitudinal asthm a trends, geographic variability, or high-risk populations.